Multiple array optoelectronic connector with integrated latch

ABSTRACT

An optical fiber link module comprises an upper connector and a lower portion. The upper connector comprises metal, and the lower portion is connected to the upper connector. The lower portion has a pair of arms for retaining a fiber optic cable.

RELATED APPLICATIONS

[0001] This application claims priority to U.S. patent application Ser.No. 09/956,771 filed on Sep. 20, 2001 entitled “Fiber Optic Transceiver,Connector, And Method of Dissipating Heat” by Johnny R. Brezina, et al.,the entire disclosure of which is incorporated by reference, herein.

[0002] This application also relates to the following applications,filed concurrently herewith:

[0003] “Optical Alignment In A Fiber Optic Transceiver”, by Johnny R.Brezina, et al. (IBM Docket No. AUS920010689US1);

[0004] “External EMI Shield For Multiple Array Optoelectronic Devices”,by Johnny R. Brezina, et al. (IBM Docket No. AUS920010690US1);

[0005] “Packaging Architecture For A Multiple Array Transceiver Using AContinuous Flexible Circuit”, by Johnny R. Brezina, et al. (IBM DocketNo. AUS920010591 US1);

[0006] “Flexible Cable Stiffener for An Optical Transceiver”, by JohnnyR. Brezina, et al. (IBM Docket No. AUS920010729US1);

[0007] “Enhanced Folded Flexible Cable Packaging for Use in OpticalTransceivers, by Johnny R. Brezina, et al. (IBM Docket No.AUS920010727US1);

[0008] “Apparatus and Method for Controlling an Optical Transceiver”, byJohnny R. Brezina, et al. (IBM Docket No. AUS920010728US1);

[0009] “Internal EMI Shield for Multiple Array Optoelectronic Devices”,by Johnny R. Brezina, et al. (IBM Docket No. AUS920010730US1);

[0010] “Mounting a Lens Array in a Fiber Optic Transceiver”, by JohnnyR. Brezina, et al. (IBM Docket No. AUS920010733US1);

[0011] “Packaging Architecture for a Multiple Array Transceiver Using aFlexible Cable”, by Johnny R. Brezina, et al. (IBM Docket No.AUS920010734US1);

[0012] “Packaging Architecture for a Multiple Array Transceiver Using aFlexible Cable and Stiffener for Customer Attachment”, by Johnny R.Brezina, et al. (IBM Docket No. AUS920010735US1);

[0013] “Packaging Architecture for a Multiple Array Transceiver Using aWinged Flexible Cable for Optimal Wiring”, by Johnny R. Brezina, et al.(IBM Docket No. AUS920010736US1); and

[0014] “Horizontal Carrier Assembly for Multiple Array OptoelectronicDevices”, by Johnny R. Brezina, et al. (IBM Docket No. AUS920010763US1).

TECHNICAL FIELD OF THE INVENTION

[0015] This invention relates generally to optoelectronic ports, andmore particularly to a multiple array optoelectronic connector with anintegrated latch.

BACKGROUND OF THE INVENTION

[0016] Optical fiber is widely used to rapidly and reliably transferdata between computer systems. In general, an optical fiber includes acore region that is coated by an annular clad. The core region has anindex of refraction greater than that of the clad, so that light istransmitted through the core by total internal refraction. Opticalfibers transmit data from an optoelectronic transducer, such as a laseror Light Emitting Diode (LED), to an optoelectronic receiver thatgenerates electrical information based upon the signal received.

[0017] The fibers are typically either threaded onto the optoelectroniccomponents or latched by the use of connectors such as MTP or MTOconnectors. In the latter instance, the connectors are usually plasticin order to accommodate the flexible elements necessary to establish aworkable latch. Most array optical devices have relatively high thermaldensities. Plastic is a relatively poor thermal conductor, however, andtherefore does not maximize the removal of heat generated by theoptoelectronic components.

SUMMARY OF THE INVENTION

[0018] The present invention is an optical fiber link module. Theoptical fiber link module comprises an optical fiber, a heat sink, and ametallic upper connector. The upper connector is integral with the heatsink and in electrical communication therewith. A lower portion isconnected to the upper connector, and is adapted to receive the opticalfiber. The lower portion has a pair of flexible arms for retaining thefiber optic cable.

[0019] It is an object of the present invention to provide an opticalfiber link module of the type described above that has increased coolingefficiency.

[0020] Another object of the present invention is to provide an opticallink module of the type described above that implements flexible snaplock arms within a cast metal connector housing.

[0021] Still another object of the present invention is to provide anoptical link module of the type described above that is simple, compact,and cost effective.

[0022] These and other advantages and features, which characterize theinvention, are set forth in the claims annexed hereto and forming afurther part hereof. However, for a better understanding of theinvention, and of the advantages and objectives attained through itsuse, reference should be made to the drawings, and to the accompanyingdescriptive matter, in which there is described exemplary embodiments ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023]FIG. 1 is a perspective view showing an optical link moduleaccording to the present invention;

[0024]FIG. 2 is a perspective view of a lower connector portion of theoptical link module; and

[0025]FIG. 3 is a perspective view of the underside of the lowerconnector portion.

DETAILED DESCRIPTION OF THE INVENTION

[0026]FIG. 1 shows the general configuration of an exemplary opticallink module 10 according to the present invention. Optical link module10 represents a fiber optic communications package which is mountedwithin a component such as a router that transfers data to and fromanother component of the router or other computer systems such asnetwork servers, mid-range computers, mainframe computers, workstations, desktop computers, portable computers, and the like. Theoptical link module 10 generally includes an upper portion 12 and alower portion 14. The upper portion 12 is preferably die cast as asingle piece of a relatively high thermal conductivity material such asaluminum, and includes an upper connector 16 and a heat sink 18.

[0027] An aluminum stiffener 20 is provided on the underside of the heatsink 18, with a flexible circuit 22 attached thereto. The flexiblecircuit may carry integrated circuit chips, resistors and otherstructure which operate to convert and route the fiber optic lightsignals from the fiber to and from other areas of the router of whichthe module 10 is a part. Although the details of such conversion androuting are considered to be well within the level of ordinary skill inthe art, further information is available in U.S. Pat. No. 6,085,006,the disclosure of which is hereby incorporated by reference. Normally,the module 10 receives serial electrical signals from a CPU, and anemitter (which may be an LED or laser) converts the serial electricalsignal to a serial optical signal for transmission through the opticalfiber. The module may also receive parallel electrical signals from theCPU, and convert the parallel electrical signal to a serial electricalsignal that is provided to the emitter. The emitter in turn converts theserial electrical signal to a serial optical signal for transmissionthrough the fiber. Similarly, incoming serial optical signals areconverted by a receiver (which may be a photodiode) to a serialelectrical signal. The serial electrical signal may be output to the CPUas a serial signal or converted to a parallel electrical signal andtransmitted to the CPU. The emitter and the receiver may also transmit aparallel signal, in which case it is possible to omit the parallel toserial conversion or it may be possible to convert a serial electricalsignal to a parallel signal for parallel optical transmission. In apreferred embodiment, signals are transmitted over the optical fibers ata frequency of about 2.5 gigahertz.

[0028] As best shown in FIGS. 2 and 3, the lower portion 14 of themodule 10 is a separate, molded thermoplastic piece having a pair ofretention arms 24 and 26. Locating pins 28 and 30 project upwardly fromthe lower portion 14, and aid in locating the lower portion 14 againstthe upper connector portion 16. The upper and lower portions of theconnector housing may be joined in any known manner, or may be joinedwith an external EMI shield such as that disclosed in U.S. patentapplication Ser. No. ______, entitled External EMI Shield For MultipleArray Optoelectronic Devices, the disclosure of which is herebyincorporated by reference. The optical module 10 may additionally oralternatively be provided with an internal EMI shield such as thatdisclosed in U.S. patent application Ser. No. ______, entitled InternalEMI Shield For Multiple Array Optoelectronic Devices, the disclosure ofwhich is also hereby incorporated by reference. In general, such shieldsare fabricated from a thin sheet of a metal, and function to inhibit thepropagation of EMI radiation from the optical module 10.

[0029] Together, the upper connector 16 and the lower portion 14 form afemale part of a standard MTP or MTO connector adapted to receive a malepart 32 situated on the distal end of a fiber optic cable 34, as shownin FIG. 1. In a preferred embodiment, the male end of the fiber includesa multiple array similar to that shown in U.S. Pat. No. 5,499,311, thedisclosure of which is hereby incorporated by reference. In general, themale part 32 is provided with detent ridges 36 that displace theretention arms 24 and 26 upon insertion, and then removably lock themale part within the female connector formed by the upper and lowerconnector housings 16 and 14.

[0030] During use, the multiple array optoelectonic components of themodule 10 generate heat. The upper connector housing 16 acts as athermal sink, and aids in the removal of heat from the internalcomponents of the optical array device by communicating the heat to theheat sink 18. In a preferred embodiment, the module 10 is cooled usingforced air. Thermal energy flows from the hot electronics to the top 16of the retainer housing, which is in the cooling airflow path. Heat isthus efficiently removed from the device, while at the same time theconnector of the module 10 is flexible enough to accommodate the snap-onretainer for the cable connector 32.

[0031] These features are achieved in a relatively simple, compact, andcost effective method. It should be appreciated that the optical linkmodule is suitable for use in other communications systems or opticaltransmission networks, such as those used in telephone service. Variousother modifications may be made to the illustrated embodiments withoutdeparting from the spirit and scope of the invention. Therefore, theinvention lies solely in the claims hereinafter appended.

What is claimed is:
 1. An optical fiber link module, comprising: anoptical fiber cable with a receiver for engaging with arms; a heat sink;a metallic upper connector integral with the heat sink and in electricalcommunication therewith; a lower portion connected to the upperconnector and adapted to retain the optical fiber cable, the lowerportion having a pair of flexible arms for engaging the receiver onfiber optic cable.
 2. The optical fiber link module of claim 1 whereinthe lower portion comprises plastic.
 3. The optical fiber link module ofclaim 1 wherein the upper portion comprises aluminum.
 4. The opticalfiber link module of claim 1 wherein the optical fiber is removable fromthe flexible arms.
 5. The optical fiber link module of claim 1 whereinthe upper connector and the lower portion form an MTP connector.
 6. Theoptical fiber link module of claim 1 wherein the upper connector and thelower portion form an MTO connector.
 7. An optical fiber link module,comprising: an upper portion including an upper connector and anintegral heat sink, the upper portion comprising a high thermal densitymetal; a plastic lower portion connected to the upper connector, thelower portion having a pair of flexible arms; and a fiber optic cableengaged with the arms.
 8. The optical fiber link module of claim 7wherein the upper connector comprises aluminum.
 9. The optical fiberlink module of claim 7 wherein the fiber optic cable is removable fromthe flexible arms.
 10. The optical fiber link module of claim 7 whereinthe upper connector and the lower portion form an MTP connector.
 11. Theoptical fiber link module of claim 7 wherein the upper connector and thelower portion form an MTO connector.
 12. The optical fiber link moduleof claim 7 wherein the fiber optic cable is removable from the flexiblearms.